The present invention relates to the field of gas analysis. In particular, the invention relates to a sampling probe that enables the measurement of gaseous species in a particle-laden flue gas.
The continuous measurement of gaseous species in fossil fuel fired boilers is beneficial to the timely control of the combustion process, as well as ancillary pollution reduction technologies. Typically, optical measurement techniques are employed when conducting measurements of gaseous species. However, combustion of fuels containing ash, such as coal, results in particle-laden flue gas that scatters transmitted energy from an optical measurement device, thereby minimizing the potential measurement distance. In many applications, such as in ductwork on coal-fired utility boilers with dimensions greater than 15 feet, the utilization of optical measurement techniques and devices becomes impractical.
Accordingly, there is a need for a sampling probe that minimizes the influence of ash particles on optical measurement devices, and enables the measurement of gaseous species over an extended path length using optical measurement techniques.